Pfizer/BioNTech effectiveness drops to 47% six months after second dose, study shows

Pfizer/BioNTech effectiveness drops to 47% six months after second dose, study shows
AFP
Tuesday 5 October 2021 - 16:21

The efficacy of the Pfizer-BioNTech Covid-19 vaccine declines from 88 percent to 46 percent, six months after the second jab, a study published on Monday in The Lancet medical journal found.

Lancet medical journal has released in August a peer review of the declining efficiency of Pfizer, showing that the two jabs prevent hospitalization and death, remaining high at 90 percent, but wanes after a period of six months.

“Reduction in vaccine effectiveness against SARS-CoV-2 infections over time is probably primarily due to waning immunity with time rather than the delta variant escaping vaccine protection.” The researchers wrote.

After the first month, the effectiveness of the vaccine against the Delta variant was 93 percent, declining to 53 percent after four months. While against other coronavirus variants, efficacy declines from 97 percent to 67 percent.

For the study, researchers relied on the electronic records of the Kaiser Permanents Southern California (KPSC) health care system. They examined the cases of 3.4 million people who are part of the KPSC health care system.

On this matter, the US Food and Drug Administration has recently authorized the use of a booster dose of the Pfizer/BioNTech vaccine for the elderly and Americans with a high risk of infection.

In response to the report of Lancet medical journal, immunologist Professor Luke O’Neill stated that healthy people under the age of 60 do not need a booster jab, however the situation could change.

“If you’re healthy and under 60 you don’t need a booster,” he added on Irish radio show Today with Claire Byrne, “But that may change when it gets to nine months out or 12 months, then that might be slightly different, that’s why the EMA (European Medicines Agency) have said just in case, anybody over 18 might be given a booster – each Government is given the job itself to decide what to do with the EMA guideline.”

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